641532231 has 20 divisors (see below), whose sum is σ = 960776784. Its totient is φ = 426600000.

The previous prime is 641532223. The next prime is 641532239. The reversal of 641532231 is 132235146.

It is an interprime number because it is at equal distance from previous prime (641532223) and next prime (641532239).

It is not a de Polignac number, because 641532231 - 2³ = 641532223 is a prime.

It is a super-2 number, since 2×641532231² = 823127206823674722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 641532195 and 641532204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641532239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 22606 + ... + 42356.

Almost surely, 2^641532231 is an apocalyptic number.

641532231 is a deficient number, since it is larger than the sum of its proper divisors (319244553).

641532231 is a wasteful number, since it uses less digits than its factorization.

641532231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20164 (or 20155 counting only the distinct ones).

The product of its digits is 4320, while the sum is 27.

The square root of 641532231 is about 25328.4865517070. The cubic root of 641532231 is about 862.4610553304.

Adding to 641532231 its reverse (132235146), we get a palindrome (773767377).

The spelling of 641532231 in words is "six hundred forty-one million, five hundred thirty-two thousand, two hundred thirty-one".